Artesyn ATCA-7470 Installation and Use (October 2014) - Manual (Page 193)

Maps and Registers
ATCA-7470 Installation and Use (6806800P15K) 193
6.4.27 Serial Management Interface (MII) Control Registers
A write access to MII Management Interface Control and Address Register starts an MII
Management Interface operation.
Table 6-68 Management interface PHY Address Register
Address Offset: 0x70
Bit Description Default Access
4:0 PHY Address 0 LPC: r/w
6:5 [6:5] Divider MDC
period MDC Frequency
0 LPC: r/w 00 4 120 ns 8.333 MHz
01 8 240 ns 4.166 MHz
10 16 480 ns 2.083 MHz
11 32 960 ns 1.046 MHz
7 0: MII disabled. MDC and MDIO are always tristated.
1: MII enabled. A write to the bit starts an operation. 0 LPC: r/w
Table 6-69 MII Management Interface Control and Address Register
Address Offset: 0x71
Bit Description Default Access
4:0 Internal PHY (Switch) register address 0 LPC: r/w
5 Turnaround status bit. The bit is set/reset after a MDIO read
operation.
0: A target device has driven MDIO low during 2nd TA bit
(normal operation)
1: No device has responded to the read operation 0 LPC:
r/w1c